The effect of wearing clothing made from cotton, water repellent cotton, and Orlon fabrics of similar constructions on the comfort of women subjects seated in an environ ment of 94° F and 80% RH was determined. In no case did the subjects state that they were hotter in one suit than in another nor were there differences in the total weight losses, evaporative weight losses, rectal temperatures, or times of onset of sweating of the subjects when clothed in the three suits. However, the water repellent cotton suit did have a lower weight gain during the tests than did the untreated suit and, conse quently, left more liquid moisture on the skin of the subjects. If the subject perspired freely, this liquid moisture on the skin was rated as a source of discomfort.

Two fabrics, 100% cotton and 100% nylon, were abraded with Stoll (inflated diaphragm), Schiefer, and Accelerotor instruments. Fabrics were given nine levels of abrasion, ranging from slight distortion of the fabric surface to fabric rupture, with each type of instrument. After abrasion, selected physical properties of the fabrics were measured and microscopic studies were made to determine the types of fabric, yarn, and fiber damage caused by the three abraders.The Stoll abrader caused severe fabric damage at very low levels of abrasion because the abradant pressure was highly localized in the center of the abraded area. The Schiefer and Accelerotor instruments caused uniform abrasion over the entire areas and abrasive damage to the fabric structure built up more slowly than with the Stoll. Both the Accelerotor and the Schiefer were more sensitive to differences in fiber toughness than was the Stoll. An imbalance between warp and filling yarn crimps had a much greater effect on the rate of damage and point of attack for the two flat abrasion testers than it had on Accelerotor abrasion. The tumbling action of the Accelerotor caused the greatest increases in fabric thickness by shaking fiber ends loose from the yarn structure and then cutting or breaking them off more slowly than did the Stoll abrader.

This paper reports the results of thermal comfort studies on women subjects wearing complete outfits of clothing made from fabrics of cotton, nylon, acetate, and Arnel. The conditions of temperature and humidity were controlled to create environments ranging from slightly cool to hot. Total weight loss, evaporative weight loss, weight gain of clothing, rectal temperature, time of onset of sweating, and skin temperature were the objective measures used. A subjective comfort vote was also taken.By use of these measures, no significant differences were found among the fiber types in relation to thermal comfort of clothing. At 94° F. and 80% relative humidity the percentages of gain in clothing weight because of perspiration absorption were related to the original weights of the clothing assemblies rather than the characteristic moisture regain levels of the natural versus the man-made fibers. Environmental temperatures of 88° and 94° F. and relative humidity of 80% had decided effects on the comfort vote and total weight losses of the subjects. Evaporative weight loss was affected by relative humidity at all temperatures used in this study.

Fabric and yarn damage caused by small increments of frictional abrasion in an Accelerotor were evaluated for three pairs of matched fabrics. Variables investigated were fiber content, blend level, weave, finish, and amount of abrasion. Quantitative measures of changes in yam and fabric properties were evaluated. Photomicrographs of fabric surfaces, yarns removed from fabrics, and of fabric cross sections were also evaluated. Fabrics with crease-resistant finishes tended to rank higher in appearance characteristics, while those with the pure finishes tended to rank higher in performance factors related to strength. Crease-resistant finishes did not necessarily accelerate abrasion damage. Evaluation of abrasion damage generally showed a relationship between increased yarn crimp and increased thread count, between loss in yarn tex and loss in yarn strength, and between loss in fabric strength and loss in yarn strength. A double rupture was observed in the breaking-strength behavior of the durable-press polyester/cotton fabrics after low levels of abrasion. This double rupture disappeared after higher abrasion levels.

Three pairs of matched fabrics, 100% cotton broadcloth, 50% polyester/50% cotton broadcloth, and 65% polyester/ 35% cotton printcloth, were abraded in an Accelerotor. One fabric of each pair had a pure finish and one had a creaseresistant finish. Eight levels of abrasion were used in the study. Fiber length distributions and fiber tensile properties were analyzed before and after abrasion to determine the effect of the abrasion on these fiber properties and to determine the mechanism by which any damage occurred. The cotton fibers tended to break into shorter lengths as a result of abrasion. This tendency was most pronounced in the resin-finished polyester/cotton printcloth, which lost virtually all of its cotton fiber content. It appeared to be least pronounced in the resin-finished cotton broadcloth, which lost many of its shortest fibers but showed no significant decrease in the number of longer fibers. The polyester fibers in the blended broadcloths showed some reductions in fiber length as a result of abrasion, while those in the printcloths did not. There were progressively greater losses in strength of the remaining fibers for both polyester and cotton fibers as a result of increasing levels of abrasion. However, much of the abrasion damage sustained by the resin-finished blended fabrics appeared to be caused by cotton fiber fracture within the internal structure of the yarn because of the unequal elongation characteristics of the cotton and polyester fibers.